ThinkPad T420 and T420i Hardware Maintenance Manual
Fourth Edition November Copyright Lenovo
Contents
Wireless LAN antenna assembly or wireless
Chapter 10. Parts list
ii ThinkPad T420 and T420i Hardware Maintenance Manual
Chapter 9. Locations
About this manual
iv ThinkPad T420 and T420i Hardware Maintenance Manual
General safety
Chapter 1. Safety information
Electrical safety
Handling devices that are sensitive to electrostatic discharge
Safety inspection guide
Grounding requirements
DANGER
Safety notices multilingual translations
DANGER
DANGER
DANGER
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DANGER
DANGER
PERIGO
Chapter 1. Safety information
PERIGO
PERIGO
PERIGO
PERIGO
DANGER
PERIGO
DANGER
DANGER
DANGER
DANGER
DANGER
DANGER
VORSICHT
VORSICHT
VORSICHT
VORSICHT
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Chapter 1. Safety information
14 ThinkPad T420 and T420i Hardware Maintenance Manual
Antes de encender el sistema despues de sustituir una FRU, compruebe que todos los tornillos, muelles y demás piezas pequeñas se encuentran en su sitio y no se encuentran sueltas dentro del sistema. Compruébelo agitando el sistema y escuchando los posibles ruidos que provocarían. Las piezas metálicas pueden causar cortocircuitos eléctricos
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Laser compliance statement multilingual translations
English Arabic Brazilian Portuguese French German Hebrew Japanese
Korean Spanish Traditional Chinese
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Chapter 1. Safety information
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Chapter 1. Safety information
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Strategy for replacing FRUs
Chapter 2. Important service information
Strategy for replacing a hard disk drive
Before replacing parts
How to use error message
Important notice for replacing a system board
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FRU identification for CTO, CMV, and GAV products
Strategy for replacing FRUs for CTO, CMV, and GAV Product definition
Dynamic Configure To Order CTO
Using PEW
1. Click Products & Service Warranty 2. Click Check Warranty Status
Using the HMM
To view the key commodities, do the following
“Diagnostics using PC-Doctor for DOS” on page
Chapter 3. General checkout
“Power system checkout” on page
This chapter presents following information
The following are not covered under warranty
What to do first
Diagnostics using PC-Doctor for DOS
Testing the computer
Checkout guide
If an error code appears, go to “Symptom-to-FRU index” on page
Detecting system information with PC-Doctor
Lenovo ThinkVantage Toolbox
Windows
Windows VistaR and Windows XP
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FRU tests
The following table shows the test for each FRU
Table 1. FRU tests
Power system checkout
Checking the ac power adapter
Checking operational charging
Checking the backup battery
Checking the battery pack
If the voltage is not correct, replace the backup battery
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If the voltage is correct, replace the system board
Restoring the factory contents by using Recovery Disc Set
Chapter 4. Related service information
Operating System Recovery Disc one disc
Applications and Drivers Recovery Disc one or more discs
Power-on password
Passwords
Hard-disk password
2. Insert the Operating System Recovery Disc into the DVD drive
How to remove the power-on password
Supervisor password
How to remove the hard-disk password
B If an SVP has been set and is known by the service technician
6. Select Master HDP
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Screen blank mode
Power management
Sleep standby mode
Hibernation mode
The system is powered off
Numeric error codes
Symptom-to-FRU index
Table 2. Numeric error codes continued
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Place the ThinkPad Notebook on a horizontal surface
Table 3. Error messages
Error messages
No-beep symptoms
Beep symptoms
LCD-related symptoms
Table 4. Beep symptoms
Symptom or error
Table 6. LCD-related symptoms
Reseat the LCD connectors
See important note for “LCD-related symptoms.”
Intermittent problems
Undetermined problems
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Chapter 5. Status indicators
Indicator
Status indicators
available while the microphone mute is on by default
Wireless LAN, Wireless WAN
The battery is being charged. When it reaches 20%, the blinking
Table 7. Status indicators continued
the battery status indicator stops blinking, but the charging may
Chapter 5. Status indicators
The ac power adapter is attached to the computer
Table 7. Status indicators continued
Table 8. Fn key combinations
Chapter 6. Fn key combinations
Key combination
Description
Table 8. Fn key combinations continued
Fn+PrtSc
Table 8. Fn key combinations continued
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Screw notices
Chapter 7. FRU replacement notices
External CRU statement to customers
Plastic to plastic
Restoring the serial number of the system unit
Retaining serial numbers
Torque driver
3. Select 2. Read S/N data from EEPROM
Reading or writing the ECA information
Retaining the UUID
MTM on rear label
Product ID on rear label
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Chapter 8. Removing and replacing a FRU
External CRU statement to customers
DANGER
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Before servicing ThinkPad T420 and T420i
1010 Battery pack
Important notice for replacing a battery pack
Removal steps of battery pack DANGER
Removal steps of ExpressCard blank bezel
1020 ExpressCard blank bezel
Removal steps of Serial Ultrabay Enhanced device or travel bezel
1030 Serial Ultrabay Enhanced device or travel bezel
Removal steps of hard disk drive and solid state drive
1040 Hard disk drive HDD and solid state drive SSD
For HDD and HDD rubber rails 7.0mm
For HDD and HDD rubber rails 9.5 mm
For SSD and spacers
Chapter 8. Removing and replacing a FRU
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Removal steps of DIMM slot cover
1050 DIMM slot cover
Removal steps of DIMM in the slot on the underside of the computer
1060 DIMM in the slot on the underside of the computer
Removal steps of PCI Express Mini Card for wireless WAN
1070 PCI Express Mini Card for wireless WAN
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Removal steps of keyboard
1080 Keyboard
3 , and then detach the connector
Installation steps of keyboard
Lift the keyboard a little in the direction shown by arrow
Chapter 8. Removing and replacing a FRU
is attached firmly
4. Make sure that the front edge of the keyboard
Removal steps of DIMM in the slot under the keyboard
1090 DIMM in the slot under the keyboard
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Removal steps of backup battery DANGER
1100 Backup battery
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Removal steps of PCI Express Mini Card for wireless LAN
1110 PCI Express Mini Card for wireless LAN
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When installing
1120 Keyboard bezel assembly, FPC cable, and Bluethooth daughter card
Step
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Screw quantity
Color
Chapter 8. Removing and replacing a FRU
When installing Make sure that the connector is attached firmly
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When installing Make sure that the connectors are attached firmly
Chapter 8. Removing and replacing a FRU
When installing Make sure that the connector is attached firmly
Removal steps of SmartCard
1130 SmartCard
Removal steps of SmartCard dummy spacer
When installing Make sure that the connector is attached firmly
Removal steps of modem daughter card MDC
1140 Modem daughter card MDC
Removal steps of speaker assembly
1150 Speaker assembly
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Removal steps of LCD unit
1160 LCD unit
Step
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Screw quantity
Color
Make sure that you attach the connectors firmly
When installing
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Removal steps of fan assembly
1170 Fan assembly
For Discrete Graphics models
For Integreted Graphics models
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For Discrete Graphics models
1a 1d 1c 1b
For Integreted Graphics models When installing
For Discrete Graphics models
For Integrated Graphics models
Make sure that the fan connector is attached firmly
Removal steps of CPU
1180 CPU
Removal steps of base cover assembly and DC-in connector cable
1190 Base cover assembly and DC-in connector cable
Step
When installing Make sure that the connector is attached firmly
Screw quantity
Color
Note Applying labels to the base cover
Wireless WAN MAC address label China mobile IMEI label
Removal steps of magnesium structure frame
1200 Magnesium structure frame
Black
M2 × 8 mm, wafer-head, nylon-coated
0.181 Nm
1.85 kgfcm
Removal steps of system board and ExpressCard slot assembly
1210 System board and ExpressCard slot assembly
For Switchable Graphics models For Integrated Graphics models
Platform Controller Hub PCH
Graphic Processing Unit GPU Discrete graphics chip
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1220 mSATA solid state drive
Step
Removal steps of mSATA solid state drive
Screw quantity
Color
Removal steps of LCD bezel assembly
2010 LCD bezel assembly
Removal steps of LED board
2020 LED board
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When installing Make sure that the connector is attached firmly
Removal steps of integrated camera
2030 Integrated camera
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Removal steps of LCD panel and LCD cable
2040 LCD panel and LCD cable
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When installing Make sure that the connector is attached firmly
Removal steps of camera cable
2050 Camera cable
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Screw quantity
Step
Color
Torque
Removal steps of hinges and LCD rear cover assembly
2070 Hinges and LCD rear cover assembly
Chapter 8. Removing and replacing a FRU
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Front view
Chapter 9. Locations
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Status indicators
Rear view
DisplayPort connector USB connector RJ-45 Ethernet connector
External monitor connector Power jack USB connector
Bottom view
Battery pack Battery pack latch DIMM slot Docking connector
LCD cover latch
This chapter contains following lists of the service parts
Chapter 10. Parts list
“Information about ac power adapters” on page “Power cords” on page
“Recovery discs” on page “Common service tools” on page
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Overall
ThinkPad b/g/n Wireless 1x1 BGN
Parts list-Overall
Intel Centrino Wireless-N
FRU Overall
FRU Overall
Table 9. Parts list-Overall continued
FRU no
CRU ID
FRU Overall
Table 9. Parts list-Overall continued
FRU no
CRU ID
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Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU Overall
Table 9. Parts list-Overall continued
FRU no
CRU ID
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Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU Overall
Table 9. Parts list-Overall continued
FRU no
CRU ID
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Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU Overall
Table 9. Parts list-Overall continued
FRU no
CRU ID
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Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU Overall
Table 9. Parts list-Overall continued
FRU no
CRU ID
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Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU Overall
Table 9. Parts list-Overall continued
FRU no
CRU ID
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Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU Overall
Table 9. Parts list-Overall continued
FRU no
CRU ID
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Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU Overall
Table 9. Parts list-Overall continued
FRU no
CRU ID
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Table 9. Parts list-Overall continued
FRU Overall
FRU no
FRU Overall
Table 9. Parts list-Overall continued
FRU no
CRU ID
Table 10. Parts list-LCD FRUs
LCD FRUs
LCD bezel assembly
FRU no
No. FRU
Table 10. Parts list-LCD FRUs continued
FRU no
2 Camera module
Table 10. Parts list-LCD FRUs continued
152 ThinkPad T420 and T420i Hardware Maintenance Manual
FRU no
FRU no
Table 10. Parts list-LCD FRUs continued
Table 11. Parts list-Keyboard
Keyboard
Netherlands
Table 11. Parts list-Keyboard continued
45N2090
45N2160
Table 12. Parts list-Miscellaneous parts
Miscellaneous parts
FRU no
Table 12. Parts list-Miscellaneous parts continued
Information about ac power adapters
Table 13. Parts list-2-pin ac power adapters
Table 14. Parts list-3-pin ac power adapters
Power cords
Table 15. Parts list-2-pin power cords
Table 16. Parts list-3-pin power cords
Recovery discs
Windows XP Professional DVDs
Windows Vista Business 32 bit SP2 DVDs
Windows Vista Home Basic 32 bit SP2 DVDs
Table 20. Parts list-Windows 7 Professional 32 bit recovery DVDs
Windows 7 Professional 32 bit DVDs
Windows 7 Professional 64 bit DVDs
4179-CTO, GBx, GEx
Windows 7 Home Premium 32 bit DVDs
Windows 7 Home Basic 32 bit DVDs
Table 24. Parts list-Windows 7 Home Premium 64 bit recovery DVDs
Table 23. Parts list-Windows 7 Home Premium 32 bit recovery DVDs
Windows 7 Home Premium 64 bit DVDs
4178-CTO, 9Fx, 9Nx, A6x, BWx, CLx, CMx, CNx 4179-CTO, GMx, GNx
Table 26. Parts list-Windows 7 Ultimate 64 bit recovery DVDs
Table 25. Parts list-Windows 7 Ultimate 32 bit recovery DVDs
Windows 7 Ultimate 32 bit DVDs
Windows 7 Ultimate 64 bit DVDs
Table 27. Parts list-Common service tools
Common service tools
Appendix A. Notices
Lenovo United States, Inc 1009 Think Place - Building One
Morrisville, NC U.S.A Attention Lenovo Director of Licensing
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Electronic emissions notices
Trademarks
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Page
Part Number 0A6000703 1P P/N 0A6000703
0A6000703
